//Copyright (c) 2012 The cwkshell Authors. All rights reserved. 
// Use of this source code is governed by a BSD-style license that can be 
// found in the LICENSE file. 
#include "cuc/src/cwkshell/browser//platform_util.h" 

#include <commdlg.h>
#include <dwmapi.h>
#include <shellapi.h>
#include <shlobj.h>

#include "base/bind.h"
#include "base/bind_helpers.h"
#include "base/files/file_path.h"
#include "base/file_util.h"
#include "base/logging.h"
#include "base/string_util.h"
#include "base/utf_string_conversions.h"
#include "base/win/registry.h"
#include "base/win/scoped_co_mem.h"
#include "base/win/scoped_comptr.h"
#include "content/public/browser/browser_thread.h"
#include "googleurl/src/gurl.h"
#include "ui/base/win/shell.h"
#include "ui/gfx/native_widget_types.h"

using content::BrowserThread;

namespace {

	void ShowItemInFolderOnFileThread(const base::FilePath& full_path) {
		DCHECK(BrowserThread::CurrentlyOn(BrowserThread::FILE));
		base::FilePath dir = full_path.DirName();
		// ParseDisplayName will fail if the directory is "C:", it must be "C:\\".
		if (dir.value() == L"" || !file_util::EnsureEndsWithSeparator(&dir))
			return;

		typedef HRESULT (WINAPI *SHOpenFolderAndSelectItemsFuncPtr)(
			PCIDLIST_ABSOLUTE pidl_Folder,
			UINT cidl,
			PCUITEMID_CHILD_ARRAY pidls,
			DWORD flags);

		static SHOpenFolderAndSelectItemsFuncPtr open_folder_and_select_itemsPtr =
			NULL;
		static bool initialize_open_folder_proc = true;
		if (initialize_open_folder_proc) {
			initialize_open_folder_proc = false;
			// The SHOpenFolderAndSelectItems API is exposed by shell32 version 6
			// and does not exist in Win2K. We attempt to retrieve this function export
			// from shell32 and if it does not exist, we just invoke ShellExecute to
			// open the folder thus losing the functionality to select the item in
			// the process.
			HMODULE shell32_base = GetModuleHandle(L"shell32.dll");
			if (!shell32_base) {
				NOTREACHED() << " " << __FUNCTION__ << "(): Can't open shell32.dll";
				return;
			}
			open_folder_and_select_itemsPtr =
				reinterpret_cast<SHOpenFolderAndSelectItemsFuncPtr>
				(GetProcAddress(shell32_base, "SHOpenFolderAndSelectItems"));
		}
		if (!open_folder_and_select_itemsPtr) {
			ShellExecute(NULL, L"open", dir.value().c_str(), NULL, NULL, SW_SHOW);
			return;
		}

		base::win::ScopedComPtr<IShellFolder> desktop;
		HRESULT hr = SHGetDesktopFolder(desktop.Receive());
		if (FAILED(hr))
			return;

		base::win::ScopedCoMem<ITEMIDLIST> dir_item;
		hr = desktop->ParseDisplayName(NULL, NULL,
			const_cast<wchar_t *>(dir.value().c_str()),
			NULL, &dir_item, NULL);
		if (FAILED(hr))
			return;

		base::win::ScopedCoMem<ITEMIDLIST> file_item;
		hr = desktop->ParseDisplayName(NULL, NULL,
			const_cast<wchar_t *>(full_path.value().c_str()),
			NULL, &file_item, NULL);
		if (FAILED(hr))
			return;

		const ITEMIDLIST* highlight[] = {
			{file_item},
		};

		hr = (*open_folder_and_select_itemsPtr)(dir_item, arraysize(highlight),
			highlight, NULL);

		if (FAILED(hr)) {
			// On some systems, the above call mysteriously fails with "file not
			// found" even though the file is there.  In these cases, ShellExecute()
			// seems to work as a fallback (although it won't select the file).
			if (hr == ERROR_FILE_NOT_FOUND) {
				ShellExecute(NULL, L"open", dir.value().c_str(), NULL, NULL, SW_SHOW);
			} else {
				LPTSTR message = NULL;
				DWORD message_length = FormatMessage(
					FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM,
					0, hr, 0, reinterpret_cast<LPTSTR>(&message), 0, NULL);
				LOG(WARNING) << " " << __FUNCTION__
					<< "(): Can't open full_path = \""
					<< full_path.value() << "\""
					<< " hr = " << hr
					<< " " << reinterpret_cast<LPTSTR>(&message);
				if (message)
					LocalFree(message);
			}
		}
	}

}  // namespace
namespace cuc{ 

	namespace platform_util {

		void ShowItemInFolder(const base::FilePath& full_path) {
			DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
			BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
				base::Bind(&ShowItemInFolderOnFileThread, full_path));
		}

		void OpenItem(const base::FilePath& full_path) {
			DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
			BrowserThread::PostTask(
				BrowserThread::FILE, FROM_HERE,
				base::Bind(base::IgnoreResult(&ui::win::OpenItemViaShell), full_path));
		}

		void OpenExternal(const GURL& url) {
			// Quote the input scheme to be sure that the command does not have
			// parameters unexpected by the external program. This url should already
			// have been escaped.
			std::string escaped_url = url.spec();
			escaped_url.insert(0, "\"");
			escaped_url += "\"";

			// According to Mozilla in uriloader/exthandler/win/nsOSHelperAppService.cpp:
			// "Some versions of windows (Win2k before SP3, Win XP before SP1) crash in
			// ShellExecute on long URLs (bug 161357 on bugzilla.mozilla.org). IE 5 and 6
			// support URLS of 2083 chars in length, 2K is safe."
			const size_t kMaxUrlLength = 2048;
			if (escaped_url.length() > kMaxUrlLength) {
				NOTREACHED();
				return;
			}

			base::win::RegKey key;
			std::wstring registry_path = ASCIIToWide(url.scheme()) +
				L"\\shell\\open\\command";
			key.Open(HKEY_CLASSES_ROOT, registry_path.c_str(), KEY_READ);
			if (key.Valid()) {
				DWORD size = 0;
				key.ReadValue(NULL, NULL, &size, NULL);
				if (size <= 2) {
					// ShellExecute crashes the process when the command is empty.
					// We check for "2" because it always returns the trailing NULL.
					// TODO(nsylvain): we should also add a dialog to warn on errors. See
					// bug 1136923.
					return;
				}
			}

			if (reinterpret_cast<ULONG_PTR>(ShellExecuteA(NULL, "open",
				escaped_url.c_str(), NULL, NULL,
				SW_SHOWNORMAL)) <= 32) {
					// We fail to execute the call. We could display a message to the user.
					// TODO(nsylvain): we should also add a dialog to warn on errors. See
					// bug 1136923.
					return;
			}
		}

#if !defined(USE_AURA)
		gfx::NativeWindow GetTopLevel(gfx::NativeView view) {
			return ::GetAncestor(view, GA_ROOT);
		}

		gfx::NativeView GetParent(gfx::NativeView view) {
			return ::GetParent(view);
		}

		bool IsWindowActive(gfx::NativeWindow window) {
			return ::GetForegroundWindow() == window;
		}

		void ActivateWindow(gfx::NativeWindow window) {
			::SetForegroundWindow(window);
		}

		bool IsVisible(gfx::NativeView view) {
			// MSVC complains if we don't include != 0.
			return ::IsWindowVisible(view) != 0;
		}
#endif

	}  // namespace platform_util
} //namespace cuc 
